Managing Ignored Files in Subversion

Introduction

Subversion (SVN) is a widely used version control system that allows teams to manage changes to source code and other files. A crucial feature of any version control system is its ability to ignore certain files or directories, keeping the repository clean and focused on essential files only. This tutorial will guide you through various methods of managing ignored files in Subversion, ensuring that unwanted files do not clutter your project.

Ignoring Files in Subversion

Ignoring files involves specifying patterns for files or directories that should be excluded from version control operations. In SVN, this is achieved using ignore properties and runtime configurations. Let’s explore the main techniques:

1. Using `svn:ignore` Property

The svn:ignore property allows you to specify file patterns to be ignored in a specific directory. This property is stored within the repository, ensuring that all collaborators have consistent ignore settings.

How to Set `svn:ignore`

To set or modify the svn:ignore property for a directory:

svn propset svn:ignore "pattern" .

Replace "pattern" with the file pattern you wish to ignore. Patterns can include wildcards, like *.log or temp/.

Applying `svn:ignore` Recursively

By default, svn:ignore is non-recursive and applies only to immediate children of the directory where it’s set. To apply patterns recursively:

svn propset svn:ignore "pattern" . --recursive

This command sets the ignore property on all subdirectories.

2. Using `svn:global-ignores` Property

SVN 1.8 introduced svn:global-ignores, a property that supports inherited patterns. This means once set, it applies to all descendant directories automatically.

How to Set `svn:global-ignores`

To apply global ignore rules:

svn propset svn:global-ignores "pattern" .

Unlike svn:ignore, this property doesn’t require the --recursive flag for inheritance.

3. Runtime Configuration

Subversion also allows you to configure ignored patterns globally on your client machine using a runtime configuration file:

Configuring Global Ignores

Edit your Subversion config file located at:

Windows (registry-based): Software\Tigris.org\Subversion\Config\Miscellany\global-ignores
Windows (file-based): C:\Users\<YourUsername>\AppData\Roaming\Subversion\config
Linux/Unix: ~/.subversion/config

Add patterns to the global-ignores section. This setup is client-side only and applies to all repositories checked out on your system.

4. Using Command-Line Tools for Ignoring Files

You can use command-line tools to list, set, or manage ignored files effectively:

Listing Unversioned and Ignored Files

To see unversioned files that match ignore patterns:

svn status --no-ignore | grep "^I"

Creating Ignore Lists Dynamically

Generate a list of files not under version control and selectively add them to the ignore property:

svn status | grep "^\?" | awk "{print \$2}" > ignoring.txt

Edit ignoring.txt to specify which files you want to ignore, then apply it using:

svn propset svn:ignore -F ignoring.txt .

Best Practices

Consistent Ignore Patterns: Use .gitignore-like files for setting multiple patterns easily.
Commit Ignore Changes: Always commit changes to ignore properties so that all team members inherit them.
Verify Ignored Files: Regularly check ignored files using svn status --no-ignore to ensure your ignore rules are effective.

Conclusion

Effectively managing ignored files in Subversion enhances repository cleanliness and ensures efficient version control. By leveraging the various methods outlined in this tutorial, you can tailor ignore settings to fit your project’s needs, whether through properties like svn:ignore, runtime configurations, or command-line tools.